First report of ‘Candidatus Phytoplasma pyri’ in Norway
In Norway, during an official survey conducted in 2016 and 2017, ‘Candidatus Phytoplasma pyri’ (associated with pear decline - EPPO A2 List) was detected for the first time. During this survey, 1123 samples were collected from pear (Pyrus communis) trees from 46 locations in 10 fruit-producing counties. During these investigations, the psyllid vectors, Cacopsylla pyri and C. pyricola, were also collected from 6 locations and tested. ‘Ca. Phytoplasma pyri’ was detected (real-time PCR) in 85 samples from 12 locations in the counties Akershus, Aust-Agder, Buskerud, Hordaland, Telemark, Vestfold and Østfold. Most detections were made in symptomless plants, but some pear trees were showing upward leaf rolling. No damage on fruit was observed. 304 psyllids were collected and ‘Ca. Phytoplasma pyri’ was detected in 21 specimens from 2 locations. Official control measures were taken. All individual plants in the nuclear stock collection were tested and infected plants were destroyed.
The pest status of ‘Candidatus Phytoplasma pyri’ in Norway is officially declared as: Present: only in some areas where host crop(s) are grown.
Sources
NPPO of Norway (2018-06).